Influence of current density on microstructure of pulse electrodeposited tin coatings

Pulse electrodeposited tin coatings on copper substrate have been synthesized from an aqueous solution containing sodium stannate (Na2SnO3.3H2O) and sodium hydroxide (NaOH). The effect of current density on surface morphology of the deposits has been investigated. As deposited coatings are characterized by X-ray diffraction, scanning electron microscopy, electron backscatter diffraction, and line profile analysis. The X-ray diffraction analysis shows that the deposits consist of tetragonal (β-Sn) structure with microcrystalline grains. The deposits plated at lower current density exhibit (110) texture which decreases with increasing current densities. The effects of current density on Cu–Sn diffusion and whisker growth of the electrodeposited tin coatings are also reported here. - Highlights: ► Pulse electrodeposition of Sn from aqueous alkaline solution without adding any organic additive. ► Effect of current density on morphology and whisker growth in tin coatings aged for 1 year. ► Solution bath is stable and can be operated over a wide range of current density.